Virulence factors and clinical patterns of multiple-clone hypermucoviscous KPC-2 producing K. pneumoniae

Abstract

Carbapenemase-producing Klebsiella pneumoniae (CRKP) are increasingly reported worldwide being necessary the local epidemiological monitoring. Our aim was to characterize the hypermucoviscous CRKP isolates collected in our hospital during a 6 months period. Carriage of the carbapenemase genes (bla _KPC, bla _NDM, bla _VIM and bla _OXA-48), extended spectrum β-lactamases (bla _SHV-2, bla _CTX-M) and the virulence genes (magA, k2A, rmpA, wabG, uge, allS, entB, ycfM, kpn, wcaG, fimH, mrkD, iutA, iroN, hly and cnf-1) were determined by multiplex-PCR. Genetic relationship among the isolates was performed by PFGE and MLST. A total of 35 isolates were recovered, being the urinary and respiratory tract the most common infection sites (34.2%). The bla _KPC-2 gene was present in all the isolates, coexisting with bla _CTX-M-2 (45.7%), bla _SHV-2 (28.6%), and bla _CTX-M-2/bla _SHV-2 (14.3%). The capsular serotype K2 corresponded with 68.6% of the isolates. Virulence factors frequency were variable [adhesins (97.1%), siderophores (94.3%) and phagocytosis resistance (wabG 48.5%, uge 80% and ycfM 57.1%)]. A total of 10 STs were identified although 40% of them clustered on ST25-CC65, and 17% to ST17. The incidence of KPC-2-producing K. pneumoniae reported by the hospital was 0.290 per 1000 admissions. In summary we described an epidemic scenario of multidrug resistant hypermucoviscous KPC-2 producing ST25 K. pneumoniae in our institution.

Keywords: Carbapenemase; Epidemiology; Infectious disease; KPC; Klebsiella pneumoniae; Microbiology; Multi-clonal.

Fig. 1

DNA finger printing by PFGE and relation to ST type in KPC-2 Klebsiella pneumoniae strains.